Vascular locating systems and methods of use

ABSTRACT

Disclosed are puncture sealing systems and methods of locating a puncture site within a vessel. The systems can include puncture locating dilators and access sheaths that are configured to locate the puncture site within a vessel so that the position of the puncture site relative to a distal end of the access sheath is known during a puncture sealing procedure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 14/063,522filed Oct. 25, 2013, which claims priority to and the benefit of U.S.Provisional Application Ser. No. 61/745,006 filed Dec. 21, 2012, andU.S. Provisional Application Ser. No. 61/846,217, filed Jul. 15, 2013,the contents of each of which are hereby incorporated by reference as ifset forth in their entirety herein.

BACKGROUND

During the use of vascular closure systems after vascular interventions,it is often important to know the location of a puncture in the vessel,and in particular, providing for exact placement of vascular sheaths.Typically, a “blood flashback” method is used to position a vasculardevice, but this technique is not feasible with catheters whose size issimilar to the vessel internal diameter (ID) due to the limited flowpossible.

SUMMARY

In an embodiment of the invention, a method of locating a puncture sitein a vessel of a patient, can comprise the steps of inserting a guidewire through the puncture site and into the vessel such that a portionof the guide wire protrudes from the vessel; inserting a proximal end ofthe guide wire into a distal end of a dilator, the dilator having aninlet hole, an outlet hole in fluid communication with the inlet hole,and a radiopaque marker proximate to the inlet hole; moving the dilatoralong the guide wire until the distal end of the dilator and the inlethole enter the vessel such that blood flows into the inlet hole and outthe outlet hole to thereby locate a position of the puncture site; afterthe position of the puncture site has been located, determining aposition of the radiopaque marker of the dilator on an imaging device;and positioning an external marker on the patient that corresponds withthe position of the radiopaque marker of the dilator determined on theimaging device to thereby provide a visual indication of the puncturesite location after the dilator is removed from the guide wire.

In accordance with another embodiment of the invention, a method oflocating a puncture site in a vessel of a patient, can comprise thesteps of inserting a guide wire through the puncture site and into thevessel such that a portion of the guide wire protrudes from the vessel;inserting a proximal end of the guide wire into a distal end of a sheathdilator that is coupled within an access channel of a sheath body, atleast one of the sheath dilator and the sheath body having an inlet holeand an outlet hole in fluid communication with the inlet hole; movingthe sheath dilator and sheath body combination along the guide wireuntil the distal end of the sheath dilator and the inlet hole enter thevessel such that blood flows into the inlet hole and out the outlet holeto thereby determine a position of the puncture site; and noting a firstvisible marking of a plurality of markings on the sheath body that isadjacent the patient's skin when the blood flows out the outlet hole.

In accordance with yet another embodiment of the invention, a method oflocating a puncture site in a vessel of a patient, can comprise thesteps of inserting a guide wire through the puncture site and into thevessel such that a portion of the guide wire protrudes from the vessel;inserting a proximal end of the guide wire into a distal end of a sheathdilator that is coupled within an access channel of a sheath body, thesheath dilator having an inlet hole; moving the sheath dilator andsheath body combination distally along the guide wire until the distalend of the sheath dilator and the inlet hole enter the vessel;confirming that the inlet hole is within the vessel by drawing fluidfrom the vessel with a syringe that is in communication with the inlethole; slightly withdrawing the sheath dilator and sheath bodycombination proximally along the guide wire; actuating the syringe todetermine whether the inlet hole is within the vessel; repeating thewithdrawing and actuating steps until the inlet hole is external to thevessel; after the repeating step, slightly move the sheath dilator andsheath body combination distally along the guide wire to therebyposition the inlet hole within the vessel; and noting a first visiblemarking of a plurality of markings on the sheath body that is adjacentthe patient's skin when the inlet hole is positioned in the vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofexample embodiments of the application, will be better understood whenread in conjunction with the appended drawings, in which there is shownin the drawings example embodiments for the purposes of illustration. Itshould be understood, however, that the application is not limited tothe precise systems and methods shown. In the drawings:

FIG. 1A is a top plan view, showing a puncture locating dilator of apuncture sealing system in accordance with an embodiment of theinvention, the puncture locating dilator having a dilator body thatdefines a blood inlet hole, a blood outlet hole, and a radiopaque markeradjacent the blood inlet hole;

FIG. 1B is a cross-sectional view of the puncture locating dilator shownin FIG. 1A through the line 1B-1B;

FIG. 1C is a top plan view, showing an access sheath of the puncturesealing system shown in FIG. 1A, the access sheath having a sheath bodyand a sheath dilator coupled within an access channel of the sheathbody;

FIG. 2A is a schematic showing the puncture locating dilator of FIG. 1positioned such that the inlet hole is disposed within a vesselproximate to a puncture site and such that an external radiopaque markerplaced on the skin is aligned with the radiopaque marker on the dilatorbody;

FIG. 2B is a schematic showing the access sheath of FIG. 1C beinginserted into the vessel;

FIG. 2C is a schematic showing the sheath dilator removed from theaccess channel and the sheath body positioned such that a radiopaquemarker near a distal end of the sheath body is aligned with the externalradiopaque marker;

FIG. 3A is a top plan view, showing a puncture locating dilator of apuncture sealing system in accordance with another embodiment of theinvention, the puncture locating dilator having dilator body thatdefines a blood inlet hole, a blood outlet hole, and a plurality ofdepth markings spaced from each other between the inlet and outletholes;

FIG. 3B is a cross-sectional view of the puncture locating dilator shownin FIG. 3A through the line 3B-3B;

FIG. 4A is a top plan view, showing an access sheath of the puncturesealing system shown in FIG. 3A, the access sheath having a sheath bodyand a sheath dilator coupled within an access channel of the sheathbody, the sheath body defining a plurality of depth markings thatcorrespond to the depth markings on the puncture locating dilator shownin FIG. 3A;

FIG. 4B is a top plan view, showing an access sheath in accordance withanother embodiment, the access sheath having a sheath body that definesa distance measured from a distal end of the sheath body to a firstdepth marker on the sheath body that is greater than that of the accesssheath shown in FIG. 4A;

FIG. 5A is a schematic showing the puncture locating dilator of FIG. 3Apositioned such that the inlet hole is disposed within a vesselproximate to a vessel puncture and at least one of the markings beingvisible above the surface of the skin;

FIG. 5B is a schematic showing the access sheath of FIG. 4A being movedinto the vessel;

FIG. 5C is a schematic showing the sheath dilator removed from theaccess channel and the sheath body positioned such that a depth markingon the sheath body that corresponds to the at least one marking on thepuncture locating dilator is visible above the surface of the skin;

FIG. 6 is a top plan view, showing an access sheath of a puncturesealing system in accordance with another embodiment of the invention,the access sheath having a sheath body and a sheath dilator coupledwithin an access channel of the sheath body, the sheath body defining aplurality of depth markings and the sheath dilator including a bloodinlet hole distal to the sheath body and a blood outlet hole proximal tothe sheath body;

FIG. 7A is a schematic showing the access sheath of FIG. 6, positionedsuch that the inlet hole is disposed within a vessel proximate to avessel puncture and at least one of the markings being visible above thesurface of the skin;

FIG. 7B is a schematic showing the access sheath of FIG. 7A, movedfurther into the vessel such that a full insertion marker on the sheathbody that is proximal to the plurality of markings is adjacent thepatient's skin;

FIG. 7C is a schematic showing the access sheath of FIG. 7B with thesheath dilator removed from the access channel and a closure devicemoved into the access channel;

FIG. 7D is a schematic showing the access sheath of FIG. 7C movedproximally such that the at least one marking noted in FIG. 7A is againvisible above the surface of the skin;

FIG. 8A is a top plan view, showing an access sheath of a puncturesealing system in accordance with another embodiment of the invention,the access sheath including a sheath body and a sheath dilator coupledwithin an access channel of the sheath body;

FIG. 8B is a top plan view of the sheath body shown in FIG. 8A, thesheath body including four blood inlet holes, a syringe in communicationwith the blood inlet holes, and a plurality of depth markings spacedbetween the syringe and blood inlet holes;

FIG. 8C is a top plan view of the sheath dilator shown in FIG. 8A, thesheath dilator having a dilator body that defines four blood flowchannels;

FIG. 9A is a schematic showing the access sheath of FIG. 8A, positionedsuch that the blood inlet hole is disposed within a vessel proximate toa vessel puncture such that the syringe can withdraw blood through theblood inlet holes, and at least one of the markings being visible abovethe surface of the skin;

FIG. 9B is a schematic showing the access sheath of FIG. 9A in aposition such that the syringe can no longer withdraw blood through theinlet holes;

FIG. 9C is a schematic showing the access sheath of FIG. 9B, movedfurther into the vessel such that a full insertion marker on the sheathbody that is proximal to the plurality of markings is adjacent thepatient's skin;

FIG. 9D is a schematic showing the access sheath of FIG. 9C with thesheath dilator removed from the access channel;

FIG. 9E is a schematic showing the access sheath of FIG. 9D with aclosure device coupled within the access channel;

FIG. 9F is a schematic showing the access sheath of FIG. 7C movedproximally such that the at least one marking is again visible above thesurface of the skin;

FIG. 10A is a schematic showing a closure device coupled within anaccess channel of a sheath body, the closure device having a pluralityof depth markings; and

FIG. 10B is a schematic showing the closure device and sheath bodycombination of FIG. 10A moved such that a depth marking of the closuredevice that corresponds to a previously noted depth marking is the firstvisible depth marking adjacent the patient's skin.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Certain terminology is used in the following description for convenienceonly and is not limiting. The words “right”, “left”, “lower” and “upper”designate directions in the drawings to which reference is made. Thewords “proximally” and “distally” refer to directions toward and awayfrom, respectively, the individual operating the system. The terminologyincludes the above-listed words, derivatives thereof and words ofsimilar import.

Referring to FIGS. 1A-2C, a puncture sealing system in accordance withan embodiment of the invention can include a puncture locating dilator10 that is configured to locate a puncture site 12 in a vessel 13 of apatient using radiopaque markers. As shown in FIGS. 1A and 1B, thepuncture locating dilator 10 is configured to be moved along a guidewire 14 toward the puncture site 12 such that the puncture locatingdilator 10 enters the vessel 13 through the puncture site 12. As thepuncture locating dilator 10 enters the vessel 13 the puncture locatingdilator 10 dilates the puncture site 12. As shown in FIG. 1C, thepuncture sealing system can further include an access sheath 18 that isalso configured to be moved along the guide wire 14 toward the puncturesite 12 and into the vessel 13 so as to further dilate the puncture site12 and subsequently provide access to the vessel 13. The access sheath18 can then receive a sealing device that is configured to seal thepuncture site 12. It should be appreciated, however, that the system caninclude additional dilators that have cross-sectional diameters that aredifferent (e.g. greater) than the diameter of the locating dilator 10but less than that of the access sheath 18 so that the puncture site 12can be gradually dilated and prepared for the access sheath 18. Both thelocating dilator 10 and the access sheath 18 include a respectiveradiopaque marker that is configured to aid in locating the puncturesite 12.

As shown in FIGS. 1A and 1B, the puncture locating dilator 10 includes adilator body 34 that is elongate along a first direction L and defines aproximal end P and a distal end D that is spaced from the proximal end Palong the first direction L. As shown in FIGS. 1A and 1B, the puncturelocating dilator 10 defines a guide channel 38 that extends through thedilator body 34 along the first direction L from the distal end Dthrough to the proximal end P. The guide channel 38 is configured toreceive the guide wire 14 such that the puncture locating dilator 10 canbe moved along the guide wire 14 toward the puncture site 12. The guidechannel 38 at the distal and proximal ends D and P can have a diameterthat is substantially equal to that of the guide wire 14 so that thepuncture locating dilator 10 can move along the guide wire 14 in acontrolled manner. As shown in FIG. 1A, the puncture locating dilator 10can further define a blood inlet hole 42 that extends through thedilator body 34 along a direction that is transverse to the firstdirection L, and a blood outlet hole 46 that extends through the dilatorbody 34 proximal to the blood inlet hole 42. The blood inlet hole 42 andthe blood outlet hole 46 are in fluid communication with each other suchthat when the blood inlet hole 42 enters the vessel 13, blood from thevessel 13 will enter the blood inlet hole 42 and exit the blood outlethole 46 to thereby indicate that the blood inlet hole 42 has entered thevessel 13. In this way, a position of the puncture site 12 can belocated or otherwise determined. In the illustrated embodiment, theblood inlet and outlet holes 42 and 46 extend into the guide channel 38such that blood entering the blood inlet hole 42 will travel through theguide channel 38, around the guide wire 14, and out the blood outlethole 46. It should be appreciated, however, that in some embodiments,the guide channel 38 and the channel through which the blood flows canbe separate and distinct from each other, as desired.

With continued reference to FIG. 1A, the puncture locating dilator 10can further include a hub 50 that extends radially out from the dilatorbody 34 between the inlet and outlet holes 42 and 46. The hub 50 can beconfigured as a handle that can be firmly grasped to thereby move thepuncture locating dilator 10 along the guide wire 14. It should beappreciated, however, that the hub 50 can be located anywhere along thedilator body 34 as desired.

With continued reference to FIG. 1A, the puncture locating dilator 10can further include a radiopaque marker 54 that is proximate to theblood inlet hole 42. In the illustrated embodiment, the radiopaquemarker 54 is a band that extends around the dilator body 34 proximal tothe blood inlet hole 42. It should be appreciated, however, that theradiopaque marker 54 can be distal to the blood inlet hole 42 as desiredand can have other configurations as desired. For example, theradiopaque marker 54 can be internally located rather than as anexternal band, as desired or can be a ball that is bored into a side ofthe body 34. The radiopaque marker 54 can be used to angiographicallylocate the puncture site 12. That is, after a position of the puncturesite 12 has been located with the blood inlet hole 42, a position of theradiopaque marker 54 can be determined on an imaging device such as afluoroscope. An external marker 62 can then be positioned on the patientthat corresponds with the position of the radiopaque marker 54determined on the imaging device to thereby provide a visual indicationof the puncture site location after the puncture locating dilator 10 hasbeen removed from the guide wire 14. As shown in FIG. 2A, the externalmarker 62 can be a radiopaque sticker that is placed directly on thepatient's skin as desired. It should be appreciated, however, that theexternal marker 62 can be placed on the patient but not directly to thepatient's skin as desired. Furthermore, it should be appreciated, thatthe external marker 62 can have other configurations as desired. Forexample, the external marker 62 can be a tag, card, clip, etc.

Now referring to FIG. 1C, the access sheath 18 includes a sheath body 60that is elongate along the first direction L and a sheath dilator 64that is coupled within an access channel 68 of the sheath body 60. Theaccess channel 68 extends through the sheath body 60 from a proximal endthrough to a distal end of the sheath body 60 and is configured toprovide an access path to the puncture site 12 after the sheath dilator64 has been removed from the access channel 68. The access sheath 18like the puncture locating dilator 10 is configured to be moved alongthe guide wire 14 toward the puncture site 12 such that the distal endof the access sheath 18 enters the vessel 13.

With continued reference to FIG. 1C, the access sheath 18 furtherincludes a radiopaque marker 72 on the sheath body 60 proximate to adistal end of the sheath body 60. In the illustrated embodiment, theradiopaque marker 72 is a band that extends around the sheath body 60.It should be appreciated, however, that the radiopaque marker 72 canhave other configurations as desired so long as it can be seen on animaging device. The radiopaque marker 72 can be used to position thesheath body 60. For example, the sheath body 60 can be positioned suchthat the radiopaque marker 72 is aligned with the external radiopaquemarker 62. As with the positioning of the puncture locating dilator 10,the access sheath 18 or at least the sheath body 60 can be positionedusing the imaging device. When aligned, the appropriate amount of sheathbody 60 will be disposed within the vessel 13 or at least the closuredevice will be properly positioned.

Similar to the puncture locating dilator 10, the sheath dilator 64includes a dilator body 84 that is elongate along the first direction Land defines a guide channel 88 that extends through the dilator body 34along the first direction L from a distal end through to a proximal endof the dilator body 84. The guide channel 88 is configured to receivethe guide wire 14 such that the access sheath 18 can be moved along theguide wire 14 toward the puncture site 12. The guide channel 88 at thedistal and proximal ends of the dilator body 84 can have a diameter thatis substantially equal to that of the guide wire 14 so that the accesssheath 18 can move along the guide wire 14 in a controlled manner. Oncethe access sheath 18 has been inserted into the vessel 13, the sheathdilator 64 can be pulled proximally from the access channel 68. At thispoint, a closure device 90 can be inserted into the access channel 68.And when the closure device 90 is properly positioned using theradiopaque marker 72, the puncture site can be sealed.

Now referring to FIGS. 2A-2C, the guide wire can be inserted through thepuncture site 12 and into the vessel 13 such that a portion of the guidewire 14 protrudes from the vessel 13. Once the guide wire 14 ispositioned, a proximal end of the guide wire 14 can be inserted into thedistal end of the puncture locating dilator 10. As shown in FIG. 2A, thepuncture locating dilator 10 can then be moved along the guide wire 14until the distal end of the puncture locating dilator 10 and the bloodinlet hole 34 enter the vessel 13 such that blood flows into the inlethole 42 and out the outlet hole 46 to thereby locate a position of thepuncture site 12. The position of the puncture site 12 can be confirmedvia feedback of blood flow exiting the blood outlet hole 46 byalternatingly inserting and retracting the puncture locating dilator 10.As shown in FIG. 2A, after the position of the puncture site 12 has beenlocated, a position of the radiopaque marker 54 of the dilator 10 can bedetermined on an imaging device and an external marker 62 can bepositioned on the patient. The external marker 62 can be positioned suchthat it corresponds with the position of the radiopaque marker 54 of thedilator 10 to thereby provide a visual indication of the puncture sitelocation after the dilator 10 is removed from the guide wire 14. Itshould be appreciated, that in some embodiments, the puncture locatingdilator 10 can be positioned over the guide wire 14 prior to the guidewire being inserted into the vessel 13.

As shown in FIG. 2B, after the puncture locating dilator 10 has beenremoved from the guide wire 14 and any subsequent dilators have beenremoved, the access sheath 18 can be moved along the guide wire 14toward the puncture site 12 such that the distal end of the accesssheath 18 enters the vessel 13 through the puncture site 12. Inparticular, the proximal end of the guide wire 14 is inserted into thedistal end of the sheath dilator 64. And then the sheath body 60 andsheath dilator 64 can be moved together along the guide wire 14 towardthe puncture site 12. Once inserted, the sheath dilator 64 can be pulledproximally such that the sheath dilator 64 is removed from the accesschannel 68.

After the sheath dilator 64 has been removed, access for a vascularclosure procedure as is detailed in PCT/US2012/061855, the disclosure ofwhich is hereby incorporated by reference herein, can be performedthrough the access channel 68. Therefore as shown in FIG. 2C, a closuredevice 90 can be moved into the access channel 68 until a distal portion92 (e.g. at least a portion of a toggle 94) of the closure device 90 isdistal to the distal end of the sheath body 60. The access sheath 18 canthen be moved such that the radiopaque marker 72 proximate to the distalend of the sheath body 60 is aligned with the external marker 62. Theradiopaque markers 72 and 62 can be aligned by viewing the markers 62and 72 on an imaging device such as a fluoroscope while the accesssheath 18 and thus the closure device 90 is being positioned. It shouldbe appreciated, however, that while the closure device 90 is preferablymoved into the access channel 68 prior to the positioning of the accesssheath 18 such that the radiopaque marker 72 is aligned with theexternal marker 62, the closure device 90 can be moved into the accesschannel 68 after the positioning of the access sheath 18, as desired.When the access sheath 18 is properly positioned, the closure device 90will be positioned such that the sealing procedure can be completed. Itshould be appreciated, that while in the illustrated embodiment, theradiopaque marker 72 is on the sheath body 60, in some embodiments, theradiopaque marker 72 can be on the closure device 90, as desired.Furthermore, it should be appreciated, that in such embodiments, theaccess sheath 18 can be pulled completely out of the vessel when theclosure device 90 is properly positioned (see e.g. FIGS. 10A and 10B).

Now in reference to FIGS. 3A-5C, a puncture sealing system in accordancewith another embodiment of the invention can include a puncture locatingdilator 110 that is configured to locate the puncture site 12 in thevessel 13 of a patient using depth markings. The depth markings of thisembodiment can either be used alone or in combination with theradiopaque markers of the embodiment shown in FIGS. 1A-2C. As shown inFIGS. 4A and 4B, the system can further include an access sheath 118that also includes depth markings that correspond to the depth markingsof the puncture locating dilator 110. The system including the puncturelocating dilator 110 and the access sheath 118 are substantially similarto the puncture locating dilator 10 and the access sheath 18 shown inFIGS. 1A-2C, and operate in a similar manner unless otherwise described.

As shown in FIGS. 3A and 3B, like the puncture locating dilator 10, thepuncture locating dilator 110 includes a dilator body 134 that iselongate along the first direction L and defines a proximal end P₂ and adistal end D₂ that is spaced from the proximal end P₂ along the firstdirection L. As shown in FIGS. 3A and 3B, the puncture locating dilator110 defines a guide channel 138 that extends through the dilator body134 along the first direction L from the distal end D₂ through to theproximal end P₂. The guide channel 138 is configured to receive theguide wire 114 such that the puncture locating dilator 110 can be movedalong the guide wire 114 toward the puncture site 12. The guide channel138 at the distal and proximal ends D₂ and P₂ can have a diameter thatis substantially equal to that of the guide wire 114 so that thepuncture locating dilator 110 can move along the guide wire 114 in acontrolled manner. As shown in FIG. 3A, the puncture locating dilator110 can further define a blood inlet hole 142 that extends through thedilator body 134 along a direction that is transverse to the firstdirection L, and a blood outlet hole 146 that extends through thedilator body 134 proximal to the blood inlet hole 142. The blood inlethole 142 and the blood outlet hole 146 are in fluid communication witheach other such that when the blood inlet hole 142 enters the vessel 13,blood from the vessel 13 will enter the blood inlet hole 142 and exitthe blood outlet hole 146 to thereby indicate that the blood inlet hole142 has entered the vessel 13. In this way, a position of the puncturesite 12 can be located or otherwise determined. In the illustratedembodiment, the blood inlet and outlet holes 142 and 146 extend into theguide channel 138 such that blood entering the blood inlet hole 142 willtravel through the guide channel 138, around the guide wire 114, and outthe blood outlet hole 146.

With continued reference to FIG. 3A, the puncture locating dilator 110can further include a hub 150 that is similar to hub 50. As shown inFIG. 3A, the hub 150 extends radially out from the dilator body 134between the inlet and outlet holes 142 and 146. The hub 150 can beconfigured as a handle that can be firmly grasped to thereby move thepuncture locating dilator 110 along the guide wire 114.

With continued reference to FIG. 3A, the puncture locating dilator 110can further include a plurality of depth markings 154 spaced from eachother along the first direction L between the inlet and outlet holes 142and 146. The depth markings 154 can be used to visually note the depthor otherwise the location of the puncture site 12 of the vessel 13 whenthe puncture locating dilator 110 has been positioned within the vessel.In the illustrated embodiment, the depth markings 154 are numbers on thedilator body 134. It should be appreciated, however, that the depthmarkings 154 can have other configurations as desired. For example, thedepth markings can be configured as symbols as desired. The depthmarkings 154 can be used to locate the puncture site 12. That is, aftera position of the puncture site 12 has been located with the blood inlethole 142, a position of a first visible marking of the plurality ofdepth markings 154 on the dilator that is adjacent the patient's skincan be noted when the blood flows. Therefore, the position of thepuncture site 12 can be known for the remainder of the procedure. Thenoted first marking can be noted with a sticker that is placed directlyon the patient's skin as desired. It should be appreciated, however,that the first depth marking can be noted using other configurations asdesired. For example, the first depth marking can be noted with a tag,card, clip, etc.

Now referring to FIG. 4A, the access sheath 118 includes a sheath body160 that is elongate along the first direction L and a sheath dilator164 that is coupled within an access channel 168 of the sheath body 160.The access channel 168 extends through the sheath body 160 from aproximal end through to a distal end of the sheath body 160 and isconfigured to provide an access path to the puncture site 12 after thesheath dilator 164 has been removed from the access channel 168. Theaccess sheath 118 like the puncture locating dilator 110 is configuredto be moved along the guide wire 114 toward the puncture site 12 suchthat the distal end of the access sheath 118 enters the vessel 13.

With continued reference to FIG. 4A, the access sheath 18 furtherincludes a plurality of depth markings 172 spaced from each other alongthe first direction L on the sheath body 160. The depth markings 172correspond to the depth markings 154 on the puncture locating dilator110 such that as the access sheath 18 is inserted into the vessel 13 thelocation of the distal end of the access sheath 118 relative to thepuncture site 12 can be known because of the depth markings 172. In theillustrated embodiment, the depth markings 172 are numbers. It should beappreciated, however, that the depth markings 172 can have otherconfigurations as desired so long as they somehow correspond to thedepth markings 154. The depth markings 172 can be used to position thesheath body 160 so that a closure device 190 that is to be moved intothe access channel 168 will be properly positioned for sealing of thepuncture site 12. For example, the sheath body 160 can be positionedsuch that a first marking of the depth markings 172 that corresponds tothe noted first visible marking on the dilator 110 is the first visiblemarking on the access sheath 118. When the first visible marking of theaccess sheath 118 corresponds to the noted first visible marking on thepuncture locating dilator 110, the appropriate amount of sheath body 160will be disposed within the vessel 13. It should be appreciated,however, that in some embodiments, the depth markings 172 can be placedon the closure device 190 rather than the sheath body 160.

As shown in FIGS. 4A and 4B, a distance d between a distal end of theaccess sheath 118 and a first marking of the plurality of depth markings172 can be varied. For example, the distance d in the embodiment shownin FIG. 4B is greater than that of the embodiment shown in FIG. 4A.Therefore, different access sheaths 118 can be used depending on theapplication. For example, in a procedure using the closure deviceillustrated in the 855 application, the access sheath 118 shown in FIG.4A may be used.

The sheath dilator 164 is similar to the sheath dilator 64 and operatesin a similar manner. Therefore, once the access sheath 118 has beeninserted into the vessel 13, the sheath dilator 164 can be pulledproximally from the access channel 168.

Now referring to FIGS. 5A-5C, the guide wire 114 can be inserted throughthe puncture site 12 and into the vessel 13 such that a portion of theguide wire 114 protrudes from the vessel. Once the guide wire 114 ispositioned, a proximal end of the guide wire 114 can be inserted intothe distal end of the puncture locating dilator 110. As shown in FIG.5A, the puncture locating dilator 110 can then be moved along the guidewire 114 until the distal end of the puncture locating dilator 110 andthe blood inlet hole 142 enter the vessel 13 such that blood flows intothe inlet hole 142 and out the outlet hole 146 to thereby locate aposition of the puncture site 12. The position of the puncture site 12can be confirmed via feedback of blood flow exiting the blood outlethole 146 by alternatingly inserting and retracting the puncture locatingdilator 10. As shown in FIG. 5A, after the position of the puncture site12 has been located, a first visible marking 154 a of the dilator 110can be noted. That is a first visible marking 154 a that is adjacent thepatient's skin can be noted. It should be appreciated, that in someembodiments, the puncture locating dilator 110 can be positioned overthe guide wire 114 prior to the guide wire being inserted into thevessel 13.

As shown in FIG. 5B, after the puncture locating dilator 110 has beenremoved from the guide wire 14 and any subsequent dilators have beenremoved, the access sheath 118 can be moved along the guide wire 114toward the puncture site 12 such that the distal end of the accesssheath 118 enters the vessel 13 through the puncture site 12. Inparticular, the proximal end of the guide wire 114 is inserted into thedistal end of the sheath dilator 164. And then the sheath body 160 andsheath dilator 164 can be moved together along the guide wire 114 towardthe puncture site 12. Once inserted, the sheath dilator 164 can bepulled proximally such that the sheath dilator 164 is removed from theaccess channel 168.

After the sheath dilator 164 has been removed, a vascular closureprocedure can be performed through the access channel 168. Therefore, aclosure device 190 can be moved into the access channel 168 until adistal portion 192 (e.g. at least a portion of a toggle 194) of theclosure device 190 is distal to the distal end of the sheath body 160.As shown in FIG. 5C the access sheath 118 can then be moved such that afirst visible marking 172 a of the sheath body 160 that is visibleadjacent the patient's skin corresponds with the noted first visiblemarking 154 a of the puncture locating dilator 110. It should beappreciated, that the closure device 190 can be moved into the accesschannel 168 either prior to or after the positioning of the accesssheath 118 such that the first visible marking 172 corresponds to thenoted marking 154. When the access sheath 118 is properly positioned,the closure device 190 will be positioned such that the sealingprocedure can be completed. It should be appreciated, that while in theillustrated embodiment, in some embodiment's the depth markings 172 areon the sheath body 160, the depth markings can be on the closure device190, as desired. Furthermore, it should be appreciated, that in suchembodiments, the access sheath 118 can be pulled completely out of thevessel 13 when the closure device 190 is properly positioned.

Now in reference to FIGS. 6-7D, a puncture sealing system in accordancewith another embodiment of the invention can include an access sheath218 having a sheath body 260 and a sheath dilator 264 coupled within anaccess channel 268 of the sheath body 260. The sheath dilator 264 can beconfigured as a puncture locating dilator such that the access sheath218, itself is configured to determine the location of the puncture site12. As in the embodiment shown in FIGS. 3A-5C, the sheath body 260includes a plurality of depth markings that can be used to determine thelocation of the puncture site 12.

As shown in FIG. 6, the sheath body 260 is elongate along the firstdirection L and the access channel 268 extends through the sheath body260 from a proximal end through to a distal end of the sheath body 260.The access channel 268 is configured to provide an access path to thepuncture site 12 after the sheath dilator 264 has been removed from theaccess channel 268. The access sheath 218 is configured to be movedalong the guide wire 214 toward the puncture site 12 such that thedistal end of the access sheath 218 enters the vessel 13.

With continued reference to FIG. 6, the access sheath 218 furtherincludes a plurality of depth markings 272 spaced from each other alongthe first direction L on the sheath body 260. The depth markings 272 areeach spaced a respective distance from the distal end of the sheath body260. Therefore, when the puncture site 12 is located with the sheathdilator 264, a first marking of the plurality of depth markings 272 canbe noted to thereby indicate to a user the location of the puncture site12 relative to the distal end of the sheath body 260. In the illustratedembodiment, the depth markings 272 are numbers. It should beappreciated, however, that the depth markings 272 can have otherconfigurations as desired. As will be described, the depth markings 272can be used to position the sheath body 260.

With continued reference to FIG. 6, the access sheath 218 can furtherinclude a full insertion marker 274 on the sheath body 260 that isproximal to the plurality of markings 272. The full insertion marker 274can be positioned on the sheath body 260 to indicate to a surgeon whenthe access sheath 218 is sufficiently positioned so that for example thesheath dilator 264 can be removed from the sheath body 260. The fullinsertion marker 274 can be a number like the depth markers 172 or canbe a symbol as desired. It should be appreciated, however, that the fullinsertion marker 274 can also be a furthest depth marker of theplurality of depth markers 272 from the distal end of the sheath body260, as desired.

The sheath dilator 264 is similar to the sheath dilator 10 and operatesin a similar manner. As shown in FIG. 6, the sheath dilator 264 includesa dilator body 234 that is elongate along a first direction L anddefines a proximal end P₃ and a distal end D₃ that is spaced from theproximal end P₃ along the first direction L. The sheath dilator 264defines a guide channel 238 that extends through the dilator body 234along the first direction L from the distal end D₃ through to theproximal end P₃. The guide channel 238 is configured to receive theguide wire 214 such that the sheath dilator 264 and sheath body 260 canbe moved along the guide wire 214 toward the puncture site 12. The guidechannel 238 at the distal end D₃ can have a diameter that issubstantially equal to that of the guide wire 214 so that the sheathdilator 264 can move along the guide wire 214 in a controlled manner. Asshown in FIG. 6, the sheath dilator 264 can further define a blood inlethole 242 that extends through the dilator body 234 along a directionthat is transverse to the first direction L, and a blood outlet hole 246that extends through the dilator body 234 proximal to the blood inlethole 242. The blood inlet hole 242 and the blood outlet hole 246 are influid communication with each other such that when the blood inlet hole242 enters the vessel 13, blood from the vessel 13 will enter the bloodinlet hole 242 and exit the blood outlet hole 246 to thereby indicatethat the blood inlet hole 242 has entered the vessel 13. In this way, aposition of the puncture site 12 can be located or otherwise determined.In the illustrated embodiment, the blood inlet and outlet holes 242 and246 extend into the guide channel 238 such that blood entering the bloodinlet hole 242 will travel through the guide channel 238, around theguide wire 214, and out the blood outlet hole 246. It should beappreciated, however, that in some embodiments, the guide channel 238and the channel through which the blood flows can be separate anddistinct from each other, as desired.

After the puncture site has been located using the sheath dilator 264, afirst visible marking 272 a on the sheath body 260 that is adjacent thepatient's skin can be noted. And after the puncture site has beenlocated and its position noted, the sheath dilator 264 can be pulledproximally from the access channel 268.

Now referring to FIGS. 7A-7D, the guide wire 214 can be inserted throughthe puncture site 12 and into the vessel 13 such that a portion of theguide wire 214 protrudes from the vessel. Once the guide wire 214 ispositioned, a proximal end of the guide wire 214 can be inserted intothe distal end of the sheath dilator 264. As shown in FIG. 7A, thesheath dilator 264 along with the sheath body 260 can then be movedalong the guide wire 214 until the distal end of the sheath dilator 264and the blood inlet hole 242 enter the vessel 13 such that blood flowsinto the inlet hole 242 and out the outlet hole 246 to thereby locate aposition of the puncture site 12. The position of the puncture site 12can be confirmed via feedback of blood flow exiting the blood outlethole 246 by alternatingly inserting and retracting the sheath dilator264 and sheath body 260 combination. As shown in FIG. 7A, after theposition of the puncture site 12 has been located, a first visiblemarking 272 a of the sheath body 260 can be noted. That is, a firstvisible marking 272 a that is adjacent the patient's skin can be noted.It should be appreciated, that in some embodiments, the access sheath218 can be positioned over the guide wire 214 prior to the guide wirebeing inserted into the vessel 13.

As shown in FIG. 7B, after the first visible depth marking 272 a hasbeen noted, the access sheath 218 can be further moved along the guidewire 214 until the full insertion marker 274 is adjacent the patient'sskin surface. At this time, the sheath dilator 264 can be pulledproximally and removed from the access channel 268. And after the sheathdilator 264 has been removed, a vascular closure procedure can beperformed through the access channel 268. Therefore, as shown in FIG. 7Ca closure device 290 can be moved into the access channel 268 until adistal portion 292 of the closure device is distal to the distal end ofthe sheath body 260 and the closure device 290 couples to the sheathbody via for example a snap fit. For example, at least a portion of atoggle 294 of the closure device can be distal to the sheath body 260when the closure device 290 is positioned within the access channel 268.As shown, in FIG. 7C, the closure device 290 can be moved along theguide wire 214 as it is being inserted into the access channel 268.

As shown in FIG. 7D, the sheath body 260 and closure device 290 can thenbe pulled proximally until the depth marking 272 a noted during thepuncture locating step becomes visible adjacent the patient's skin. Whenthe access sheath 218, or at least the sheath body 260 is properlypositioned, the closure device will be positioned such that the sealingprocedure can be completed. For example, the toggle 294 can be deployedinto the vessel 13 so that the puncture site 12 can be sealed. It shouldbe appreciated, that in some embodiments the closure device 290 caninclude the depth markings and the sheath body 260 can be pulled suchthat the sheath body 260 exits the vessel 13 and a first depth markingon the closure device 290 that corresponds to the noted depth marking isvisible.

Now in reference to FIGS. 8A-9F, a puncture sealing system in accordancewith another embodiment of the invention can include an access sheath318 having a sheath body 360 and a sheath dilator 364 coupled within anaccess channel 368 of the sheath body 360. The access sheath 318 canfurther include a syringe 366 that is coupled to the sheath body 360 andis configured to aid in determining the location of the puncture site12. As in the embodiment shown in FIGS. 6-7D, the sheath body 360includes a plurality of depth markings that can be used to determine thelocation of the puncture site 12.

As shown in FIGS. 8A and 8B, the sheath body 360 is elongate along thefirst direction L and the access channel 368 extends through the sheathbody 360 from a proximal end through to a distal end of the sheath body360. The access channel 368 is configured to provide an access path tothe puncture site 12 after the sheath dilator 364 has been removed fromthe access channel 368. The access sheath 318 is configured to be movedalong the guide wire 314 toward the puncture site 12 such that thedistal end of the access sheath 318 enters the vessel 13.

With continued reference to FIGS. 8A and 8B, the access sheath 318further includes a plurality of depth markings 372 spaced from eachother along the first direction L on the sheath body 360. The depthmarkings 372 are each spaced a respective distance from the distal endof the sheath body 360. Therefore, when the puncture site 12 is located,a first marking of the plurality of depth markings 372 can be noted tothereby indicate to a user the location of the puncture site 12 relativeto the distal end of the sheath body 360. In the illustrated embodiment,the depth markings 372 are numbers. It should be appreciated, however,that the depth markings 372 can have other configurations as desired. Aswill be described, the depth markings 372 can be used to position thesheath body 360.

With continued reference to FIGS. 8A and 8B, the access sheath 318 canfurther include a full insertion marker 374 on the sheath body 360 thatis proximal to the plurality of markings 372. The full insertion marker374 can be positioned along the sheath body 360 to indicate to a surgeonwhen the access sheath 318 is sufficiently positioned so that the sheathdilator 364 can be removed from the sheath body 360. The full insertionmarker can be a number like the depth markers 372 or can be a symbol asdesired. It should be appreciated, however, that the full insertionmarker 374 can also be a furthest depth marker of the plurality of depthmarkers 372 from the distal end of the sheath body 360, as desired.

As shown in FIG. 8B, the access sheath 318 can further include at leastone such as a plurality of blood inlet holes 342 that extend through thesheath body 360 and into the access channel 368. The blood inlet holes342 are disposed distal to the depth markings 372 and are adjacent thedistal end of the sheath body 360. The blood inlet holes 342 are incommunication with the syringe 366 such that when the blood inlet holes342 are positioned within the vessel 13, blood from the vessel can bewithdrawn by the syringe 366. In particular, the syringe 366 can bereleasably attached to a tube 380 that extends from the sheath body 360.The tube 380 can include a valve 384 that is configured to have an openposition whereby blood can exit the tube 380 into the syringe 366 and aclosed position whereby blood is unable to exit the tube 380. When inthe closed position, the syringe 366 can be removed.

Now referring to FIG. 8C, the sheath dilator 364 includes a dilator body334 that is elongate along a first direction L and defines a proximalend P₄ and a distal end D₄ that is spaced from the proximal end P₄ alongthe first direction L. The sheath dilator 364 defines a guide channel338 that extends through the dilator body 334 along the first directionL from the distal end D₄ through to the proximal end P₄. The guidechannel 338 is configured to receive the guide wire 314 such that thesheath dilator 364 and sheath body 360 can be moved along the guide wire314 toward the puncture site 12. The guide channel 338 at the distal andproximal ends D₄ and P₄ can have a diameter that is substantially equalto that of the guide wire 314 so that the sheath dilator 364 can movealong the guide wire 314 in a controlled manner. As shown in FIG. 8C,the sheath dilator 364 can further define a plurality of fluid channels346 that are configured to be a conduit that directs blood from theinlet holes 342 to an outlet hole that is in fluid communication withthe tube 380. As shown in FIG. 8C, the fluid channels 346 are elongatealong the first direction L and are in communication with respectiveblood inlet holes 342 when the sheath dilator 360 is coupled within theaccess channel 368. The blood inlet holes 342 and the syringe 366 are influid communication with each other such that when the blood inlet holes342 enter the vessel 13, blood from the vessel 13 can be withdrawn fromthe vessel by the syringe 366 thereby indicating that at least one ofthe blood inlet holes 342 has entered the vessel 13. In this way, aposition of the puncture site 12 can be located or otherwise determined.

After the puncture site has been located using the syringe 366, a firstvisible marking 372 a on the sheath body 360 that is adjacent thepatient's skin can be noted. And after the puncture site has beenlocated and its position noted, the sheath dilator 364 can be pulledproximally from the access channel 368.

Now referring to FIGS. 9A-9F, the guide wire 314 can be inserted throughthe puncture site 12 and into the vessel 13 such that a portion of theguide wire 314 protrudes from the vessel. Once the guide wire 314 ispositioned, a proximal end of the guide wire 314 can be inserted intothe distal end of the sheath dilator 364. As shown in FIG. 9A, thesheath dilator 364 along with the sheath body 360 can then be movedalong the guide wire 314 until the distal end of the sheath dilator 364and the blood inlet holes 342 enter the vessel 13. Once positioned, thesyringe 366 can be actuated so as to draw blood from the vessel 13,through the fluid flow channels of the sheath dilator 364 and into thesyringe 366.

Once it has been confirmed that the blood inlet holes 342 are within thevessel, the sheath dilator 364 and the sheath body 360 combination canbe slightly withdrawn proximally along the guide wire 314. Again, thesyringe 366 can be actuated to determine whether the blood inlet holes342 are still within the vessel 13. As shown in FIG. 9B, the withdrawingand actuating steps can be repeated until the inlet holes 342 areexternal to the vessel 13 such that fluid flow to the syringe 366 is notpossible or significantly slowed when the syringe 366 is actuated. Itshould be appreciated, that the syringe 366 can be actuated by drawingblood from the vessel 13 only or by drawing blood from the vessel 13 andsubsequently purging it back into the vessel 13, as desired.

After it has been determined that the blood inlet holes 342 are externalto the vessel 13, the sheath dilator 364 and sheath body combination 360can be slightly moved distally along the guide wire 314 to thereby againposition the inlet holes 342 within the vessel 13 as shown n FIG. 9A.The syringe 366 can once again be actuated to confirm that the inletholes 342 are positioned within the vessel 13. At this time, after theposition of the puncture site 12 has been located, the first visiblemarking 372 a of the sheath body 360 can be noted. That is, a firstvisible marking 372 that is adjacent the patient's skin can be noted.

As shown in FIGS. 9C and 9D, after the first visible depth marking 372has been noted, the syringe 366 can be removed and the access sheath 318can be further moved along the guide wire 314 until the full insertionmarker 374 is adjacent the patient's skin surface. At this time, thesheath dilator 364 can be pulled proximally and removed from the accesschannel 368 as shown in FIG. 9D. And after the sheath dilator 364 hasbeen removed, a vascular closure procedure can be performed through theaccess channel 368. Therefore, as shown in FIG. 9E a closure device 390can be moved into the access channel 368 until a distal portion 392 ofthe closure device is distal to the distal end of the sheath body 360and the closure device 390 couples to the sheath body. For example, atleast a portion of a toggle 394 of the closure device can be distal tothe sheath body 360 when the closure device 390 is positioned within theaccess channel 368. As shown, in FIG. 9E, the closure device 390 can bemoved along the guide wire 314 as it is being inserted into the accesschannel 368. It should be appreciated, however, that in someembodiments, the guide wire 314 is removed along with the sheath dilator364. And in such an embodiment, the closure device 390 is positionedwithin the access channel 318 without the use of a guide wire 314.

As shown in FIG. 9F, the sheath body 360 and closure device 390 can thenbe pulled proximally until the depth marking 372 a noted during thepuncture locating step becomes visible adjacent the patient's skin. Whenthe access sheath 318 or at least the sheath body 360 is properlypositioned, the closure device will be positioned such that the sealingprocedure can be completed. For example, the toggle 394 can be deployedinto the vessel 13 so that the puncture site 12 can be sealed. It shouldbe appreciated, that in some embodiments the closure device 390 caninclude the depth markings and the sheath body 360 can be pulled suchthat the sheath body 360 exits the vessel 13 and a first depth markingon the closure device 390 that corresponds to the noted depth marking isvisible.

FIGS. 10A and 10B show an embodiment whereby the closure device includesthe depth markings and/or radiopaque marker and the sheath body ispulled completely out of the vessel when the closure device is beingaligned. As shown in FIG. 10A, a closure device 490 can be moved into asheath body 460 such that the closure device 490 extends out a distalend of the sheath body 460. In particular, the closure device 490 can bemoved into the access channel of the sheath body 460 such that theclosure device couples to the sheath body and a plurality of depthmarkings 472 on the closure device 490 are exposed distal to the sheathbody 460. Once the closure device 490 is coupled to the sheath body 460,the sheath body can be pulled proximally such that the sheath body 460exits the vessel 13 and such that a first depth marking on the closuredevice 490 that corresponds to the depth marking noted during locationof the puncture site is visible adjacent the patient's skin. At thispoint the closure device 490 will be in position to seal the puncturesite. It should be appreciated, however, that the closure device 490 canalternatively or in addition to include a radiopaque band 473 that canbe used to position the closure device 490 by aligning the radiopaqueband 473 with an external marker 474. It should also be appreciated,that while sheath body 460 has been completely removed from the vessel13 when the closure device 490 is positioned, in some embodiments, thesheath body 460 can remain within the vessel 13 when the closure device490 is positioned.

While the foregoing description and drawings represent the preferredembodiment of the present invention, it will be understood that variousadditions, modifications, combinations and/or substitutions may be madetherein without departing from the spirit and scope of the invention asdefined in the accompanying claims. In particular, it will be clear tothose skilled in the art that the invention may be embodied in otherspecific forms, structures, arrangements, proportions, and with otherelements, materials, and components, without departing from the spiritor essential characteristics thereof. One skilled in the art willappreciate that the invention may be used with many modifications ofstructure, arrangement, proportions, materials, and components, whichare particularly adapted to specific environments and operativerequirements without departing from the principles of the invention. Inaddition, features described herein may be used singularly or incombination with other features. For example, features described inconnection with one component may be used and/or interchanged withfeatures described in another component. The presently disclosedembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims, and not limited to the foregoing description.

It will be appreciated by those skilled in the art that variousmodifications and alterations of the invention can be made withoutdeparting from the broad scope of the appended claims. Some of thesehave been discussed above and others will be apparent to those skilledin the art. For example, the device shown in FIG. 6 can include a sheathbody that defines a blood inlet hole similar to the embodiment shown inFIG. 8A. Further, it should be appreciated, that in some embodiments,the guide wire is removed along with the sheath dilator. And that insuch an embodiment, the closure device is positioned within the accesschannel without the use of a guide wire.

What is claimed:
 1. A method of locating a puncture site in a vessel ofa patient, the method comprising the steps of: inserting a guide wirethrough the puncture site and into the vessel such that a portion of theguide wire protrudes from the vessel; inserting a proximal end of theguide wire into a distal end of a dilator, the dilator having an inlethole, an outlet hole in fluid communication with the inlet hole, and aradiopaque marker proximate to the inlet hole; moving the dilator alongthe guide wire until the distal end of the dilator and the inlet holeenter the vessel such that blood flows into the inlet hole and out theoutlet hole to thereby locate a position of the puncture site; after theposition of the puncture site has been located, determining a positionof the radiopaque marker of the dilator on an imaging device; andpositioning an external marker on the patient that corresponds with theposition of the radiopaque marker of the dilator determined on theimaging device to thereby provide a visual indication of the puncturesite location after the dilator is removed from the guide wire.
 2. Themethod of claim 1, wherein the external marker is an external radiopaquemarker.
 3. The method of claim 2, further comprising the steps of:removing the dilator from the guide wire; moving an access sheath alongthe guide wire toward the puncture site such that a distal end of theaccess sheath enters the vessel through the puncture site.
 4. The methodof claim 3, wherein the access sheath includes a sheath body and asheath dilator coupled within an access channel of the sheath body, andwherein the step of moving the access sheath comprises moving the sheathbody and sheath dilator together along the guide wire.
 5. The method ofclaim 4, further comprising the step of removing at least the sheathdilator from the sheath body.
 6. The method of claim 5, furthercomprising the step of: moving a closure device into the access channeluntil a distal portion of the closure device is distal to the distal endof the sheath body.
 7. The method of claim 6, further comprising thestep of moving the sheath body and closure device combination such thata radiopaque marker on the sheath body or the closure device is alignedwith the external marker.
 8. The method of claim 7, wherein the step ofmoving the sheath body and closure combination comprises viewing theradiopaque marker of the sheath body on the imaging device to therebyalign the radiopaque marker of the sheath body or closure device withthe external radiopaque marker.
 9. The method of claim 7, wherein thestep of moving the sheath body and closure combination comprises movingthe sheath body and closure combination such that a distal end of thesheath body is removed from the vessel.
 10. The method of claim 3,wherein (i) the dilator further includes a plurality of markings spacedfrom each other between the inlet and outlet holes and (ii) the accesssheath further includes a plurality of markings spaced from each otherbetween the distal end of the access sheath and a proximal end of theaccess sheath, the markings of the access sheath corresponding to themarking of the dilator, and the method further comprising the steps of:noting a first visible marking on the dilator when the blood flows outthe outlet hole; and wherein the step of moving the access sheathcomprises moving the access sheath until a marking of the plurality ofmarkings on the access sheath that corresponds to the noted firstvisible marking on the dilator is the first visible marking on theaccess sheath.
 11. The method of claim 1, wherein the imaging device isa fluoroscope.
 12. The method of claim 1, wherein the second insertingstep is performed prior to the first inserting step.